When a motor boat having an outboard drive unit, such as an inboard/outboard motor or an outboard motor, is transported by means of a trailer or the like, it is necessary to maintain the outboard drive unit in a tilted position to prevent the lower portion of the unit from contacting the ground during transportation. Irregularities, such as bumps and potholes, in the road can cause the boat and trailer to bounce up and down and the lower portion of the outboard drive unit to come into contact with the road surface. Therefore, sufficient clearance must be maintained between the lower portion of the drive unit and the road surface to compensate for such irregularities.